Self-aligning actuator for door-operated switch

ABSTRACT

An actuator system for operating a switch is described herein. The actuator system can include a shaft of a handle assembly. The shaft couples to a handle and a male coupling element and has a number of positions. Further, a coupling body of a switch assembly can be positioned in the number of positions. The coupling body engages the switch and has a female coupling element, which has a slotted portion that receives the male coupling element and an angled terminus that aligns the shaft to a first position as the shaft couples to the coupling body. The slotted portion receives and engages the male coupling element when the shaft is coupled to the coupling body. The slotted portion prevents the male coupling element from disengaging when the coupling body is in a second position, and disengages the male coupling element when the coupling body is in the first position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of and claims priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 13/331,603, entitled“Self-Aligning Actuator For Door-Operated Switch,” filed Dec. 20, 2011,which claims priority under 35 U.S.C. § 119 to U.S. Provisional PatentApplication Ser. No. 61/426,438, titled “Self-Aligning Actuator forThrough Door Operated Disconnect Switch” and filed on Dec. 22, 2010. Theentire contents of each of the foregoing applications are herebyincorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to actuating multiple featuresof a device, and more particularly to systems, methods, and devices foractuating one or more features of a device located within anexplosion-proof enclosure using a keypad located outside theexplosion-proof enclosure.

BACKGROUND

Explosion-proof receptacle housings and enclosure systems are used inmany different industrial applications. Such explosion-proof receptaclehousing and enclosure systems may be used, for example, in militaryapplications, onboard ships, assembly plants, power plants, oilrefineries, petrochemical plants, and other harsh environments. Attimes, the equipment (e.g., variable frequency drives (VFDs)) locatedinside such explosion-proof receptacle housing and enclosure systems isused to control motors and other industrial equipment. Other equipmentthat operates on a switch and/or uses electricity may also be locatedinside an explosion-proof enclosure.

At times, a user may need to operate a switch, located inside theexplosion-proof enclosure, to change a mode of operation of one or morecomponents inside the explosion-proof enclosure. A handle or knob,mechanically coupled to the switch located inside the explosion-proofenclosure, may be located on an outer surface (e.g., on the door) of theexplosion-proof enclosure. In such a case, the user may operate thehandle or knob to change the position of the switch without opening theexplosion-proof enclosure.

SUMMARY

In general, in one aspect, the disclosure relates to an actuator systemfor operating a switch. The actuator system can include a shaft of ahandle assembly, where the shaft can be positioned in a number ofpositions. The shaft can include a first shaft end portion for couplingto a handle and a second shaft end portion that includes a male couplingelement. The actuator system can further include a coupling body of aswitch assembly, where the coupling body can be positioned in the samenumber of positions. The coupling body can include a first coupling endportion for engaging the switch and a second coupling end portion thatincludes a female coupling element. The female coupling element includesa slotted portion and an angled terminus, where the slotted portionreceives the male coupling element of the second shaft end portion.Also, the angled terminus of the female coupling element aligns, usingthe male coupling element, the shaft to a first position as the shaftcouples to the coupling body. Further, the slotted portion receives andengages the male coupling element when the shaft is coupled to thecoupling body. Also, the number of positions corresponds to a number ofswitch positions. Further, when the shaft is coupled to the couplingbody, the slotted portion prevents the male coupling element fromdisengaging when the shaft and the coupling body are in a secondposition, and the slotted portion disengages the male coupling elementwhen the shaft and the coupling body are in the first position.

In another aspect, the disclosure can generally relate to a method foroperating a switch. The method can include rotating a handle, mounted onan outer surface of a door coupled to an enclosure body, from a firstposition to a second position. The method can also include separating,after rotating the handle to the second position, the door from theenclosure body. The handle is coupled to a shaft that includes a firstshaft end portion for coupling to the handle and a second shaft endportion. Also, the second shaft end portion includes a male couplingelement that can align with a female coupling element of a firstcoupling end portion of a coupling body. Further, the coupling bodyincludes a second coupling end portion for engaging the switch. Also,the female coupling element includes a slotted portion and an angledterminus, where the slotted portion can receive and engage the malecoupling element of the second shaft end portion when the shaft iscoupled to the coupling body. Further, the positions correspond to anumber of switch positions. Also, the slotted portion prevents the malecoupling element from disengaging when the shaft and the coupling bodyare in the first position. Further, the slotted portion disengages themale coupling element when the shaft and the coupling body are in thesecond position.

These and other aspects, objects, features, and embodiments of thepresent invention will be apparent from the following description andthe appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate only exemplary embodiments of a self-aligningactuator for a door-operated switch and are therefore not to beconsidered limiting of its scope, as the invention may admit to otherequally effective embodiments. The elements and features shown in thedrawings are not necessarily to scale, emphasis instead being placedupon clearly illustrating the principles of the exemplary embodiments.Additionally, certain dimensions or positions may be exaggerated to helpvisually convey such principles. In the drawings, reference numeralsdesignate like or corresponding, but not necessarily identical,elements.

FIGS. 1 and 2 show explosion-proof enclosures in which one or moreexemplary embodiments of a self-aligning actuator for a door-operatedswitch may be implemented.

FIGS. 3A and 3B show various examples of a handle and a switch positionindicator in accordance with one or more exemplary embodiments of aself-aligning actuator for a door-operated switch.

FIG. 4 shows an exploded side view of a handle assembly in accordancewith one or more exemplary embodiments.

FIG. 5 shows an exploded side view of a switch assembly in accordancewith one or more exemplary embodiments.

FIGS. 6A-6D show a side view of an actuator system that includes aself-aligning actuator for a door-operated switch in accordance with oneor more exemplary embodiments.

FIG. 7 shows a flowchart of a method for operating a switch using aself-aligning actuator for a door-operated switch in accordance with oneor more exemplary embodiments.

FIGS. 8A through 8G show an example in accordance with one or moreexemplary embodiments.

FIGS. 9A through 9C show an example of a configuration of a malecoupling element and a female coupling element in accordance with one ormore exemplary embodiments.

FIGS. 10A and 10B show an example of a configuration of a male couplingelement and a female coupling element in accordance with one or moreexemplary embodiments.

FIGS. 11A and 11B show an example of a configuration of a male couplingelement and a female coupling element in accordance with one or moreexemplary embodiments.

DETAILED DESCRIPTION

Exemplary embodiments of a self-aligning actuator for a door-operatedswitch will now be described in detail with reference to theaccompanying figures. Like elements in the various figures are denotedby like reference numerals for consistency.

In the following detailed description of exemplary embodiments of aself-aligning actuator for a door-operated switch, numerous specificdetails are set forth in order to provide a more thorough understandingof a self-aligning actuator for a door-operated switch. However, it willbe apparent to one of ordinary skill in the art that a self-aligningactuator for a door-operated switch may be practiced without thesespecific details. In other instances, well-known features have not beendescribed in detail to avoid unnecessarily complicating the description.Further, certain descriptions (e.g., top, bottom, side, end, interior,inside) are merely intended to help clarify aspects of a self-aligningactuator for a door-operated switch and are not meant to limitembodiments of a self-aligning actuator for a door-operated switch.

In general, exemplary embodiments of an actuator system provide systems,devices, and methods for using a self-aligning actuator for adoor-operated switch mounted inside an explosion-proof enclosure.Specifically, exemplary embodiments of a self-aligning actuator for adoor-operated switch provide for preventing a door of theexplosion-proof enclosure from being opened when the switch is in acertain position because the self-aligning actuator remains engageduntil the position of the switch changes. The actuator system describedherein includes a handle assembly (including a handle and shaft) and aswitch assembly (including a switch and a coupling body).

While the exemplary embodiments discussed herein are with reference toexplosion-proof enclosures, other types of non-explosion-proofenclosures (e.g., junction boxes, control panels, lighting panels, motorcontrol centers, switchgear cabinets, relay cabinets) or any other typeof enclosure may be used in conjunction with exemplary embodiments of aself-aligning actuator for a door-operated switch. An enclosure mayinclude a cover (also called a door) and an enclosure body, as describedbelow.

A user may be any person that interacts with the explosion-proofenclosure or equipment controlled by one or more components of theexplosion-proof enclosure. Specifically, a user may operate a switchhandle (also merely called a handle) of a door-operated switch to changea position of the switch located inside the explosion-proof enclosure.As used herein, a handle may also be called an arm, an elongated arm, aknob, or any other suitable designation. A user may also, or in thealternative, open and/or close a door of an explosion-proof enclosure.Examples of a user may include, but are not limited to, an engineer, anelectrician, an instrumentation and controls technician, a mechanic, anoperator, a consultant, a contractor, and a manufacturer'srepresentative.

In one or more exemplary embodiments, the switch located inside theexplosion-proof enclosure is configured to control one or morecomponents. A component may be associated with, and/or located within,the explosion-proof enclosure. A component may be a VFD, sensor, wiring,terminal, switch, handle, indicating light, duct, and/or other element.

In one or more exemplary embodiments, an explosion-proof enclosure (alsoknown as a flame-proof enclosure) is an enclosure that is configured tocontain an explosion that originates inside the enclosure. Further, theexplosion-proof enclosure is configured to allow gases from inside theenclosure to escape across joints of the enclosure and cool as the gasesexit the explosion-proof enclosure. The joints are also known as flamepaths and exist where two surfaces meet and provide a path, from insidethe explosion-proof enclosure to outside the explosion-proof enclosure,along which one or more gases may travel. A joint may be a mating of anytwo or more surfaces. Each surface may be any type of surface, includingbut not limited to a flat surface, a threaded surface, and a serratedsurface.

In one or more exemplary embodiments, an explosion-proof enclosure issubject to meeting certain standards and/or requirements. For example,the National Electrical Manufactures Association (NEMA) sets standardsby which an enclosure must comply in order to qualify as anexplosion-proof enclosure. Specifically, NEMA Type 7, Type 8, Type 9,and Type 10 enclosures set standards by which an explosion-proofenclosure within a hazardous location must comply. For example, a NEMAType 7 standard applies to enclosures constructed for indoor use incertain hazardous locations. Hazardous locations may be defined by oneor more of a number of authorities, including but not limited to theNational Electric Code (e.g., Class 1, Division I) and Underwriters'Laboratories, Inc. (e.g., UL 698). For example, a Class 1 hazardous areaunder the National Electric Code is an area in which flammable gases ofvapors may be present in the air in sufficient quantities to beexplosive.

As a specific example, NEMA standards for an explosion-proof enclosureof a certain size or range of sizes may require that in a Group B,Division 1 area, any flame path of an explosion-proof enclosure must beat least 1 inch long (continuous and without interruption), and the gapbetween the surfaces cannot exceed 0.0015 inches. Standards created andmaintained by NEMA may be found at www.nema.org/stds and are herebyincorporated by reference.

FIGS. 1 and 2 depict an explosion-proof enclosure 100 in which one ormore exemplary embodiments of a self-aligning actuator for adoor-operated switch may be implemented. In one or more exemplaryembodiments, one or more of the components shown in FIGS. 1 and 2 may beomitted, repeated, and/or substituted. Accordingly, exemplaryembodiments of an explosion-proof enclosure should not be consideredlimited to the specific arrangements of components shown in FIGS. 1 and2.

Referring now to FIG. 1, an example of an explosion-proof enclosure 100in a closed position is shown. The enclosure cover 102 is secured to theenclosure body 124 by a number of fastening devices 118 located at anumber of points around the perimeter of the enclosure cover 102. In oneor more exemplary embodiments, a fastening device 118 may be one or moreof a number of fastening devices, including but not limited to a bolt(which may be coupled with a nut), a screw (which may be coupled with anut), and a clamp. In addition, one or more hinges 116 are secured toone side of the enclosure cover 102 and a corresponding side of theenclosure body 124 so that, when all of the fastening devices 118 areremoved, the enclosure cover 102 may swing outward (i.e., an openposition) from the enclosure body 124 using the one or more hinges 116.In one or more exemplary embodiments, there are no hinges, and theenclosure cover 102 is separated from the enclosure body 124 when all ofthe fastening devices 118 are removed.

The enclosure cover 102 and the enclosure body 124 may be made of anysuitable material, including metal (e.g., alloy, stainless steel),plastic, some other material, or any combination thereof. The enclosurecover 102 and the enclosure body 124 may be made of the same material ordifferent materials.

In one or more exemplary embodiments, on the end of the enclosure body124 opposite the enclosure cover 102, one or more mounting brackets 120are affixed to the exterior of the enclosure body 124 to facilitatemounting the enclosure 100. Using the mounting brackets 120, theenclosure 100 may be mounted to one or more of a number of surfacesand/or components, including but not limited to a wall, a controlcabinet, a cement block, an I-beam, and a U-bracket.

The enclosure cover 102 may include one or more features that allow foruser interaction while the enclosure 100 is sealed in the closedposition. As shown in FIG. 1, one or more indicating lights (e.g.,indicating light 1 106, indicting light 2 108) may be located on theenclosure cover 102. Each indicating light may be used to indicate astatus of a feature or process associated with equipment inside theenclosure 100. For example, an indicating light may show a constantgreen light if a motor controlled by a VFD inside the enclosure 100 isoperating. As another example, an indicating light may flash red when amotor controlled by a VFD inside the enclosure 100 has a problem (e.g.,tripped circuit, VFD overheats, overcurrent situation). As anotherexample, an indicating light may show a constant red light when anelectromagnetic pulse caused by an explosion inside the enclosure 100has resulted. An indicating light may be made of one or more materials(e.g., glass, plastic) using one or more different lighting sources(e.g., light-emitting diode (LED), incandescent bulb).

In one or more exemplary embodiments, the enclosure cover 102 may alsoinclude a handle 112 that allows a user to operate a switch (not shown)located inside the explosion-proof enclosure 100 while theexplosion-proof enclosure 110 is closed. Those skilled in the art willappreciate that the handle 112 may be used for any type of switch. Eachposition (e.g., OFF, ON, HOLD, RESET) of the switch may be indicated bya switch position indicator 114 positioned adjacent to the handle 112 onthe outer surface of the enclosure cover 102. A switch associated withthe handle 112 and the switch position indicator 114 may be used toelectrically and/or mechanically isolate, and/or change the mode ofoperation of, one or more components inside or associated with theexplosion-proof enclosure 100. For example, the handle 112 may point to“OFF” on the switch position indicator 114 when a disconnect switchlocated inside the explosion-proof enclosure 100 is disengaged. In sucha case, all equipment located inside the explosion-proof enclosure 100,as well as the equipment (e.g., a motor) controlled by the equipmentlocated inside the explosion-proof enclosure 100, may be without power.

Referring now to FIG. 2, an example of an explosion-proof enclosure 100in an open position in accordance with one or more exemplary embodimentsis shown. The explosion-proof enclosure 100 is in the open positionbecause the enclosure cover (not shown) is not secured to the enclosurebody 124. The hinges 116 attached to the left side of the enclosure body124 are also attached to the left side of the enclosure cover, which isswung outward from the enclosure body 124. Because the explosion-proofenclosure 100 is in the open position, the components of theexplosion-proof enclosure 100 are visible to a user.

As described above with respect to FIG. 1, the enclosure body 124includes two or more mounting brackets 120. In addition, in one or moreexemplary embodiments, the enclosure body 124 includes an enclosureengagement surface 210, against which the enclosure cover meets when theexplosion-proof enclosure 100 is in the closed position. A number offastening device apertures 220 are shown around the enclosure engagementsurface 210, where each of the fastening device apertures 220 areconfigured to receive a fastening device 118 that traverses through theenclosure cover 102, as described above with respect to FIG. 1. Thenumber of fastening device apertures 220 may vary, depending on one ormore of a number of factors, including but not limited to the size ofthe fastening device apertures 220, a standard that the explosion-proofenclosure 100 meets, and the type of fastening device 118 used. Thenumber of fastening device apertures 220 may be zero.

In one or more exemplary embodiments, the explosion-proof enclosure 100of FIG. 2 includes a mounting plate 202 that is affixed to the back ofthe inside of the explosion-proof enclosure 100. The mounting plate 202may be configured to receive one or more components such that the one ormore components are affixed to the mounting plate 202. The mountingplate 202 may include one or more apertures configured to receivesecuring devices that may be used to affix a component to the mountingplate 202. The mounting plate 202 may be made of any suitable material,including but not limited to the material of the enclosure body 124. Inone or more exemplary embodiments, some or all of the one or morecomponents may be mounted directly to an inside wall of theexplosion-proof enclosure 100 rather than to the mounting plate 202.

In one or more exemplary embodiments, a VFD 206 is affixed to themounting plate 202 inside the explosion-proof enclosure 100. The VFD 206may include any components used to drive a motor and/or other deviceusing variable control signals for controlled starts, stops, and/oroperations of the motor and/or other devices. Examples of components ofa VFD include, but are not limited to, discrete relays, a programmablelogic controller (PLC), a programmable logic relay (PLR), anuninterruptible power supply (UPS), and a distributed control system(DCS). In one or more exemplary embodiments, one or more components ofthe VFD may replace the VFD. For example, the VFD may be substituted byone or more PLCs, one or more PLRs, one or more UPSs, one or more DCSs,and/or other heat-generating components.

In one or more exemplary embodiments, a switch 208 is affixed to themounting plate 202 inside the explosion-proof enclosure 100. The switch208 may be configured to electrically and/or mechanically isolate,and/or change the mode of operation of, one or more components locatedinside the explosion-proof enclosure 100 and/or one or more componentslocated outside the explosion-proof enclosure 100. The switch 208 may beany type of switch, including but not limited to a disconnect switch, atest switch, a reset switch, an indicator switch, and a relay switch.For example, the switch 208 may be a disconnect switch that is used tocut off power to all components in the explosion-proof enclosure 100 andall devices located outside the explosion-proof enclosure 100 that arecontrolled by the components inside the explosion-proof enclosure 100.As another example, the switch 208 may be a bypass switch that is usedto deactivate a protection scheme (e.g., a relay) or some otherparticular component or group of components located inside theexplosion-proof enclosure 100.

The switch 208 may further be configured to receive, through mechanicaland/or electrical means, a directive to change states (e.g., open,closed, hold) from a component located on the enclosure cover. Forexample, if the enclosure cover includes a handle (as described abovewith respect to FIG. 1), then a switch handle shaft (also merely calleda shaft) 232 may extend from the handle through the enclosure cover to aswitch coupling 230 of the switch 208. When the explosion-proofenclosure 100 is in the closed position, the shaft 232 couples with theswitch coupling (also merely called a coupling) 230, and switch 208 maybe operated by operating the handle located outside the explosion-proofenclosure, as described above with respect to FIG. 1.

In one or more exemplary embodiments, one or more relays (e.g., relay212) are affixed to the mounting plate 202 inside the explosion-proofenclosure 100. A relay 212 may be configured to control one or moreoperations of one or more components located in, or associated with, theexplosion-proof enclosure 100. Specifically, a relay 212 may, throughone or more relay contacts, allow electrical current to flow and/or stopelectrical current from flowing to one or more components in theenclosure 100 based on whether a coil of the relay 212 is energized ornot. For example, if the coil of the relay 212 is energized, then acontact on the relay may be closed to allow current to flow to energizea motor. The relay 212 may be activated based on a timer, a current, avoltage, some other suitable activation method, or any combinationthereof. The relay 212 may also be configured to emit a signal when acondition has occurred. For example, the relay 212 may flash a red lightto indicate that the VFD 206 is in an alarm state.

In one or more exemplary embodiments, wiring terminals 214 are affixedto the mounting plate 202 inside the explosion-proof enclosure 100.Wiring terminals 214 are a series of terminals where one terminal iselectrically connected to at least one other terminal in the series ofterminals while remaining electrically isolated from the remainingterminals in the series of terminals. In other words, two or moreterminals among the series of terminals act as a junction point wheremultiple wires may be electrically connected through the joinedterminals.

In one or more exemplary embodiments, one or more entry holes 216 mayextend through one or more sides (e.g., bottom) of the enclosure body124. Each entry hole 216 may be configured to allow cables and/or wiringfor power, control, and/or communications to pass through from outsidethe explosion-proof enclosure 100 to one or more components inside theexplosion-proof enclosure 100. An entry hole 216 may be joined with aconduit and coupling from outside the explosion-proof enclosure 100 toprotect the cables and/or wiring received by the entry hole 216 and tohelp maintain the integrity of the explosion-proof enclosure 100 throughthe entry hole 216.

FIGS. 3A and 3B show various examples of a handle assembly in accordancewith one or more exemplary embodiments of a self-aligning actuator for adoor-operated switch. In each case, the handle assemblies shown in FIGS.3A and 3B are mounted on the outside of an explosion-proof enclosure.Each of these handle assemblies is described below. Exemplaryembodiments of handle assemblies for a self-aligning actuator for adoor-operated switch are not limited to the configurations shown inFIGS. 3A and 3B and discussed herein.

FIG. 3A shows a frontal view of handle assembly 302 mounted on a surface306 (e.g., a door) of an explosion-proof enclosure. The handle assembly302 shown in FIG. 3A includes an elongated arm 316 that is used torotate a pointer 310 around an axis secured by a fastening device 312.The elongated arm 316 (also generally called a handle) may be coupled toand aligned with the pointer 310, as shown in FIG. 3A. The pointer 310points to two or more designations listed on the switch positionindicator 304.

In one or more exemplary embodiments, the switch position indicator 304remains stationary and affixed to the surface 306 of the explosion-proofenclosure, adjacent to the pointer 310. The switch position indicatormay include a number of designations, where each designation correspondsto a position of the switch. In this example, the switch positionindicator 304 includes two designations of “ON” and “OFF,” whichcorrespond to “ON” and “OFF” switch positions of a switch (not shown).In such a case, the switch may be a disconnect switch.

The range of motion of the elongated arm 316 (and thus the pointer 310)may be limited by a guard 314. The guard 314 may be coupled between thesurface 306 and the elongated arm 316/pointer 310 using the fasteningdevice 312. In this example, the guard 314 limits the range of motion ofthe elongated arm 316 to approximately 90°. The limits on the range ofmotion of the elongated arm 316 may correspond to the two positions (orthe two end positions, if there are more than two positions) of thecorresponding switch located inside the explosion-proof enclosure.

FIG. 3B shows a frontal view of a handle assembly 322 mounted on asurface 326 (e.g., a door) of an explosion-proof enclosure. The handleassembly 322 shown in FIG. 3B includes a knob 334 (also generally calleda handle) that has a base 330 and a raised portion 336. The raisedportion 336 of the knob 334 is configured to allow a user to turn theknob 334 of the handle assembly 322. The raised portion 336 of the knob334 includes a pointer 332, which points to two or more designationslisted on the switch position indicator 324. The switch positionindicator 324 remains stationary and affixed to the surface 306 of theexplosion-proof enclosure. In this example, the switch positionindicator 324 includes two designations of “START/RUN” and “STOP.”

As described above with respect to FIG. 3A, the range of motion of theknob 334 (and thus the pointer 332) in FIG. 3B may be limited. Whilethere is no guard of similar component visible on the surface 326 of theexplosion-proof enclosure, the range of motion of the knob 334 may belimited by a guard located inside the base 330 or coupled to the knob334 on the surface 326 inside the explosion-proof enclosure. In thisexample, the range of motion of the knob 334 is approximately 180°. Thelimits on the range of motion of the knob 334 may correspond to the twopositions (or the two end positions, if there are more than twopositions) of the corresponding switch located inside theexplosion-proof enclosure.

In one or more exemplary embodiments, a flame path is formed where thehandle assembly 322 (or components coupled thereto) traverses anaperture in the wall of the explosion-proof enclosure. For each handleassembly shown in FIGS. 3A and 3B, the materials (e.g., plastic, metal,wood, rubber, a composite material, fiberglass) used for the variouscomponents (e.g., knob, elongated arm, pointer, guard) are suitable formaintaining the integrity of an explosion-proof enclosure while alsoretaining functional reliability for the task performed by suchcomponent. Further, for each handle assembly shown in FIGS. 3A and 3B,some or all of the handle assembly may be fixedly coupled to the surfaceand/or aperture of the explosion-proof enclosure using one or morecoupling techniques, including but not limited to bolting, welding,mating threads, using epoxy, brazing, press fitting, mechanicallyconnecting, using a flat joint, and using a serrated joint.

FIG. 4 shows an exploded view of a handle assembly 400 of an actuatorsystem for a self-aligning actuator for a door-operated switch inaccordance with one or more exemplary embodiments. The switch assembly400 shown in FIG. 4 is described below. Features, elements, and/orcomponents shown but not described and/or labeled in FIG. 4 aredescribed and/or labeled above with respect to FIGS. 3A and 3B.Exemplary embodiments of a self-aligning actuator for a door-operatedswitch are not limited to the configurations shown in FIG. 4 anddiscussed herein.

A pointer 410, fastening device 412, guard 414, and elongated arm 416,substantially similar to the keypad of FIG. 3A, are shown in FIG. 4.Between the pointer 410 and the guard 414, hidden from view when thehandle assembly 400 is assembled, is a bearing 440, which traverses thelarge apertures in the guard 414, spring return plate 442, spring 444,and door of the explosion-proof enclosure (not shown).

One end of the handle shaft 450 is coupled to a handle (in this case,the elongated arm 416) of the handle assembly. Specifically, one end ofthe handle shaft 450 is coupled to the sealing device 446 and isreceived into the bottom end of the bearing 440 to complete the handleassembly 400. The other end of the handle shaft 450 is coupled to a malecoupling element 452. The male coupling element 452 is configured tocouple to a female coupling element (described below) of the switchassembly (described below).

In one or more exemplary embodiments, when the handle (in this example,the elongated arm 416) is rotated about the axis formed using thefastening device 412, the handle shaft 450, and in particular the malecoupling element 452, rotates in a corresponding manner. When the handleassembly is coupled to the switch assembly, the handle shaft 450 and therest of the handle assembly may move among two or more positions thatcorrespond to each position of the switch (defined below).

The handle shaft 450 of the handle assembly 400 may be configured in oneof a number of different ways. Specifically, the male coupling element452 may have one of a number of different configurations. Examples ofthe shape of the male coupling element 452 may include, but are notlimited to, squared, rounded, slotted, angled, and planar. The handleshaft 450, including the male coupling element 452, may be made of oneor more materials (e.g., metal, plastic) suitable to withstand theoperating conditions (e.g., torque, temperature, pressure) that mayexist inside an explosion-proof enclosure when a switch position ischanged using exemplary embodiments.

FIG. 5 shows an exploded view of switch assembly 500 of an actuatorsystem in accordance with one or more exemplary embodiments. The switchassembly 500 includes a coupling body 529 that includes a femalecoupling element 530 and a switch shaft 531. In one or more exemplaryembodiments, the switch shaft 531 of the coupling body 529 is insertedinto the coupling receiver 534 to couple to and engage the switch 532.One end of the female coupling element 530 may be configured to coupleto the male coupling element of the shaft of the handle assembly. Theother end of the female coupling element 530 may include a shaft that isconfigured to couple to and engage the switch 532. The female couplingelement 530 also rotates as the switch 532 moves from one position toanother position.

The female coupling element 530 may have one of a number of differentconfigurations. Specifically, the female coupling element 530 may beconfigured to complement the shape of the male coupling element of theshaft of the handle assembly. Examples of the shape of the femalecoupling element 530 may include, but are not limited to, squared,rounded, slotted, angled, and planar. For example, the female couplingelement 530 may have a slotted portion as well as an angled terminus(upper lip) that aligns, as the shaft couples to the coupling body, amale coupling element with the slotted portion of the female couplingelement 530.

The coupling body 529, including the female coupling element 530, may bemade of one or more materials (e.g., metal, plastic) suitable towithstand the operating conditions (e.g., torque, temperature, pressure)that may exist inside an explosion-proof enclosure when a switchposition is changed using exemplary embodiments.

FIGS. 6A-6D show a cross-sectional side view of an actuator system 600that includes a self-aligning actuator for a door-operated switch inaccordance with one or more exemplary embodiments. The exemplaryactuator system 600 shown in FIGS. 6A and 6B are described below.Features shown but not described and/or labeled in FIGS. 6A-6D aredescribed and/or labeled above with respect to FIGS. 1 through 5.Exemplary embodiments of an actuator system are not limited to theconfigurations shown in FIGS. 6A-6D and discussed herein.

Generally stated, the handle shaft 650 of the handle assembly traversesan opening in the door 607 (also called a cover) of the enclosure.Further, the switch 632 and the coupling body are positioned within theenclosure, and the handle (elongated arm 616 in FIGS. 6A-6D) is locatedon the outer surface of the door 607 outside the enclosure. The actuatorsystem 600 shown in FIG. 6A and FIG. 6C includes a handle assembly thatis mounted on the surface 606 of the door 607 outside theexplosion-proof enclosure. Specifically, the handle assembly includes afastening device 612, guard 614, and elongated arm 616, substantiallysimilar to the corresponding components described above with respect toFIG. 3A. The handle assembly also includes a bearing 640, a handle shaft650, and a male coupling element 652, substantially similar to thecorresponding components described above with respect to FIG. 4.

The actuator system 600 also includes a switch assembly, which includesa coupling body 629 and a switch 632. The coupling body 629 includes afemale coupling element 630 and a coupling shaft 631 that couples to theswitch 632. The components of the switch assembly in FIGS. 6A-6D aresubstantially similar to the corresponding components described abovewith respect to FIG. 5.

When the door 607 is not closed, the switch 632 is in the “open”position. In one or more exemplary embodiments, one or more safetyfeatures (e.g., mechanical devices, electronic locking mechanisms) areincorporated with the switch 632 so that the switch must be in the“open” position when the door 607 is not closed. For example, atorsional spring may be incorporated into the handle assembly toposition the handle in a position substantially close to the “off”position (or some other predetermined position). In such a case, thetorsional spring may be used in conjunction with the self-alignmentfeature described above to reduce the amount of wear on the componentsof the handle assembly and the switch assembly as the door is closed(the handle assembly aligns with the switch assembly) a number of times.

In FIG. 6A, the door 607 is hingedly coupled to the enclosure body 660by one or more hinges 690 located on one side (in this example, the leftside) of the enclosure body 660. As shown in FIG. 6A, the door 607 tothe explosion-proof enclosure is slightly ajar from the enclosure body660 of the explosion-proof enclosure. In this case, the door 607 isabout to be closed (i.e., coupled to the enclosure body 660 of theexplosion-proof enclosure). Thus, the handle shaft 650 (and specificallythe male coupling element 652) of the handle assembly is coupled to thecoupling body 629 (and specifically the female coupling element 630) ofthe switch assembly. The female coupling element 630 in this case has aslotted portion 633, substantially similar to the slotted portion 633 ofthe female coupling element described above with respect to FIG. 5.Here, the slotted portion 633 extends across the width of the femalecoupling element 630 and continues down most of the length of the femalecoupling element 630.

As the male coupling element 652 in FIG. 6A approaches the femalecoupling element 630, the terminus (top edge) of the female couplingelement 630 aligns the male coupling element 652 (and thus the handleshaft 650 and the corresponding handle assembly) to the “open” position.Thus, as the door 607 continues to close, the male coupling element 652is oriented properly to slide within and toward the bottom of theslotted portion 633 of the female coupling element 630. For this tooccur, the fastening devices 662 must be removed or withdrawn, as shownin FIG. 6A, so as not to engage both the door 607 and the body 660 ofthe explosion-proof enclosure.

When the door 607 is closed against (coupled to) the enclosure body 660,as shown in FIG. 6B, the fastening devices 662 (e.g., bolts) couple thedoor 607 to the body 660 of the explosion-proof enclosure. Further, themale coupling element 652 is positioned within and toward the bottom ofthe slotted portion 633 of the female coupling element 630. In thiscase, as the handle assembly rotates, the switch 632 changes position(e.g., from “open” to “closed”) based on the coupling of the handleshaft 650 to the coupling body 629 (or, more specifically, the couplingof the male coupling element 652 to the slotted portion 633 of thefemale coupling element 630). In other words, the slotted portion 633 ofthe female coupling element 630 receives and engages the male couplingelement 652 when the handle shaft 650 is coupled to the coupling body629.

In one or more exemplary embodiments, when the door 607 is closed, theaxis of the handle assembly (i.e., along the length of the shaft) is notlinear with or parallel to the axis of the switch assembly (i.e., alongthe length of the female coupling element). In such a case, when theelongated arm 616 is rotated (thus changing the position of the handleshaft 650, the coupling body 629, and the switch 632 from the “open”position to another position), the non-linear alignment of the shaft andthe coupling body 629 causes the male coupling element 652 to remainfixedly coupled to the coupling body 629. Further, or in thealternative, as shown in FIGS. 6C and 6D, the arced path the door 607takes when the door opens from the enclosure body 660 due to the hingedconnection on one side of the enclosure body 660 between the door 607and the enclosure body 660 allows the male coupling element 652 todecouple from the coupling body 629 when the male coupling element 652and the coupling body 629 are oriented in a specific position (e.g.,coinciding with the switch in the open position).

In other words, as shown in FIG. 6A, when the shaft is coupled to thecoupling body 629 and when the fastening devices 662 are removed orsufficiently withdrawn, the slotted portion 633 of the female couplingelement 630 prevents the male coupling element 652 from disengaging fromthe slotted portion 633 when the handle shaft 650, the coupling body629, and the switch 632 are in a position other than the “open”position. Thus, the cover 607 of the enclosure cannot be opened(separated from the enclosure body 660) when the handle (elongated arm616) is in the “closed” position. Similarly, in one or more exemplaryembodiments, when the handle shaft 650 is coupled to the coupling body629, the slotted portion 633 of the female coupling element 630 allowsthe male coupling element 652 to disengage from the slotted portion 633when the handle shaft 650, the coupling body 629, and the switch 632 arein the “open” position, as shown in FIGS. 6C and 6D.

The male coupling element 652 and/or coupling body 629 may have one ormore features, either in addition to or instead of one or more featuresdescribed above, that are used to prevent the male coupling element 652from disengaging from the slotted portion 633 when the shaft, thecoupling body, and the switch 632 are in a position other than the“open” position and/or to allow the male coupling element 652 todisengage from the slotted portion 633 when the handle shaft 650, thecoupling body 629, and the switch 632 are in the “open” position. Forexample, as described more fully with respect to FIGS. 9A through 9Cbelow, the male coupling element may include a slot formed therein, andthe female coupling element may further include a pin extendingorthogonally therefrom. In such a case, when the shaft is coupled to thecoupling body, the pin may be positioned within the slot when the shaft,the coupling body, and the switch are in the closed position, and thepin may be positioned outside the slot when the shaft, the couplingbody, and the switch are in the open position.

As another example, the male coupling element may have a linear slotformed therein, and the female coupling element may further include aprotruding linear component extending orthogonally therefrom thatcorresponds to the dimensions of the linear slot of the male couplingelement. In such a case, when the shaft is coupled to the coupling body,the protruding linear component may be positioned within the linear slotwhen the shaft, the coupling body, and the switch are in the closedposition. Further, the protruding linear component may be disengagedfrom the linear slot when the shaft, the coupling body, and the switchare in the open position.

In one or more exemplary embodiments, a flame path (e.g., flame path 692in FIG. 6A) is formed between the bearing 640 and the wall of theaperture in the door 607. In other words, the gap between the bearing640 and the wall of the aperture in the door 607 is tight enough so asto cool combustible gases while exiting from inside the explosion-proofenclosure. One or more other flame paths may exist, in place of or inaddition to the flame path 692 discussed above, at other locations inand around the switch assembly.

FIG. 7 shows a flowchart of a method for operating a switch locatedinside an explosion-proof enclosure in accordance with one or moreexemplary embodiments. While the various steps in this flowchart arepresented and described sequentially, one of ordinary skill willappreciate that some or all of the steps may be executed in differentorders, may be combined or omitted, and some or all of the steps may beexecuted in parallel. Further, in one or more of the exemplaryembodiments of the invention, one or more of the steps described belowmay be omitted, repeated, and/or performed in a different order. Inaddition, a person of ordinary skill in the art will appreciate thatadditional steps, omitted in FIG. 7, may be included in performing thismethod. Accordingly, the specific arrangement of steps shown in FIG. 7should not be construed as limiting the scope of the invention.

In Step 702, a cover is coupled to an enclosure body. In one or moreexemplary embodiments, the cover includes a handle, which is mounted onan outer surface of the cover. The cover may be coupled to the enclosurebody using a plurality of fastening devices that traverse a plurality offastening device apertures along a perimeter of the cover and an outersurface of the enclosure body. The cover may further be hingedly coupledto the enclosure body by one or more hinges located on one side of theenclosure body. The handle may be part of a handle assembly that alsoincludes a shaft having a first shaft end portion for coupling to thehandle and a second shaft end portion. The shaft may traverse an openingin the cover, where the switch and a coupling body are positioned withinthe enclosure body.

The second shaft portion of the shaft may include a male couplingelement that aligns with a female coupling element of a first couplingend portion of a coupling body of a switch assembly. The coupling bodymay include a second coupling end portion for engaging the switch. Thefemale coupling element may include a slotted portion and an angledterminus.

The angled terminus of the female coupling element may align, using themale coupling element, the shaft to one of a number of positions as theshaft couples to the coupling body. For example, as the cover is coupledto the enclosure body, the male coupling element may contact the angledterminus of the female coupling element. In such a case, as the covercontinues to move closer to the enclosure body, the angled terminusrotates the male coupling element so that the male coupling elementaligns with the slotted portion of the female coupling element. Theslotted portion of the female coupling element may receive and engagethe male coupling element of the second shaft end portion after theangled terminus aligns the shaft and when the shaft is coupled to thecoupling body.

In one or more exemplary embodiments, the switch is in one position(e.g., an open position) when the cover is coupled to the enclosurebody. The handle may be in any position when the cover is coupled to theenclosure body. While the cover is coupled to the enclosure body, thehandle is aligned to the corresponding position of the switch using theangled terminus of the female coupling element and the male couplingelement.

Once the cover is coupled to the enclosure body, the position of thehandle corresponds to the position of the switch. In one or moreexemplary embodiments, a switch position indicator may be affixed to theouter surface of the cover adjacent to the handle. The switch positionindicator may include a number of designations that correspond to theswitch positions. When the cover is coupled to the enclosure body, theresulting enclosure may be an explosion-proof enclosure.

In Step 704, the handle is rotated from a second position to a firstposition. Once the cover is coupled to the enclosure body, the slottedportion may prevent the male coupling element from disengaging when theshaft and the coupling body (and so also the switch) are in one or morepredetermined positions. In one or more embodiments, the first positionof the handle corresponds to a closed switch position, and wherein thesecond position of the handle corresponds to an open switch position.For example, if the switch is rotated from an open position (a secondposition) to a closed position (a first position), then the slottedportion prevents the male coupling element from disengaging. The covermay not be separated from the enclosure body when the handle is in thefirst position.

In one or more exemplary embodiments, the male coupling element may alsoinclude a slot formed therein. Further, the female coupling elementfurther may include a pin extending orthogonally therefrom. In such acase, the pin may be positioned within the slot when the handle is inthe first position. Further, the pin may be positioned outside the slotwhen the handle is in the second position.

In Step 706, the handle is rotated from the first position to the secondposition. In one or more exemplary embodiments, the slotted portiondisengages the male coupling element when the shaft and the couplingbody (and so also the switch) are in the second position. For example,if the second position of the switch is an open position, then theslotted portion disengages the male coupling element.

In Step 708, the cover is separated from the enclosure body. In one ormore exemplary embodiments, the cover separates from the enclosure bodywhen the plurality of fastening devices are removed from the pluralityof fastening device apertures and when the handle is in the secondposition. In one or more exemplary embodiments, the switch is adisconnect switch, where the switch positions include an open positionand a closed position, and wherein the designations on the switchposition indicator include on and off. In such a case, the firstposition corresponds to a closed switch position and an on switchposition indicator designation, and the second position corresponds toan open switch position and an off switch position indicatordesignation.

The following description (in conjunction with FIGS. 1 through 7)describes a few examples in accordance with one or more exemplaryembodiments. The examples are for an actuator system for operating aswitch located inside an explosion-proof enclosure. Terminology used inFIGS. 1 through 7 may be used in the example without further referenceto FIGS. 1 through 7.

EXAMPLE 1

Consider the following example, shown in FIGS. 8A through 8G, whichdescribes an actuator system 800 in accordance with one or moreexemplary embodiments described above. FIG. 8A shows a side view of aportion of a handle assembly and a switch assembly. Specifically, theportion of the handle assembly shown in FIGS. 8A through 8G include ahandle shaft 850, where the handle shaft 850 includes a male couplingelement 852. The portion of the switch assembly shown in FIGS. 8Athrough 8G includes a coupling body 829, which includes a switch shaft834 and a female coupling element 830. The female coupling element 830has a slotted portion 833 (shown in FIG. 8E) that has a depth and awidth. The slotted portion 833 originates at the top end of the femalecoupling element 830 and runs along the width of the female couplingelement 830. Further, the top end of the female coupling element 830includes an angled terminus 831 (upper lip) that, in this case, slopesslightly from the top of the female coupling element 830 toward thebottom of the female coupling element 830. As described above, theangled terminus 831 is configured to align, as the handle shaft 850couples to the female coupling element 830, the male coupling element852 with the slotted portion 833 of the female coupling element 830.

The coupling body 829 also includes a switch shaft 834 that isconfigured to engage and couple to the switch. The switch shaft 834 isfixedly coupled to the coupling body 829, so that as the coupling body829 rotates (as may be caused by rotating the handle (not shown) of thehandle assembly when the handle shaft 850 is coupled to the couplingbody 829) along its vertical axis, the switch shaft 834 likewise rotatesalong its vertical axis. As the switch shaft 834 rotates, the positionof the switch (not shown) changes.

The male coupling element 852 has a width, shown in FIG. 8A. As shown inFIG. 8A, the handle shaft 850 (and more specifically the male couplingelement 852) is not aligned with the slotted portion of the femalecoupling element 830. For example, the switch of the switch assembly maybe in the open position, while the handle of the handle assembly may bein the closed position. Further, as shown in FIGS. 8A through 8E, thevertical axis of the coupling body 829 is substantially parallel to andsubstantially in line with the vertical axis of the handle shaft 850.One or more hinges (not shown) are located on one side of the enclosurebody (not shown) and are used to hingedly couple the door (not shown) tothe enclosure body. In this example, the one or more hinges are locatedon the left side of each of FIGS. 8A through 8E.

While the handle shaft 850 is not aligned with the female couplingelement 830 in FIG. 8A, the handle shaft 850 of the handle assembly isbeginning to couple to the coupling body 829 of the switch assembly. Asa result, as the male coupling element 852 of the handle assemblycontacts the top of the angled terminus 831 of the female couplingelement 830, the slope of the angled terminus 831 induces the malecoupling element 852 to rotate to the right (in a counterclockwisedirection, as shown in FIGS. 8B, 8C, and 8G). In one or more preferredembodiments, the male coupling element 852 includes a rounded bottomside (as shown in FIGS. 8A-8G) that helps induce the male couplingelement 852 to rotate when the rounded bottom side of the male couplingelement 852 contacts the angled terminus 831. The male coupling element852 and/or the angled terminus 831 may have one or more of a number ofother shapes that similarly induce the male coupling element 852 torotate into a proper orientation with regard to the slotted portion 833when the male coupling element 852 contacts the angled terminus 831.Thus, the angled terminus 831 aligns the handle shaft 850 to a positionthat matches the position of the switch. For example, if the switch (andthus the coupling body 829) is in the open position and the handle (andthus the handle shaft 850) is in the closed position, then as the handleshaft 850 of the handle assembly couples to the coupling body 829 of theswitch assembly, the angled terminus 831 aligns the handle shaft 850 ofthe handle assembly to the open position by rotating the male couplingelement 852.

FIGS. 8C and 8G show a cross-sectional top view and a side view,respectively, of the actuator system 800 as the handle shaft 850 of thehandle assembly couples to the coupling body 829 of the switch assembly.Here, the male coupling element 852 of the handle shaft 850 rotatescounter-clockwise along the angled terminus 831 toward alignment withthe slotted portion 833 of the female coupling element 830 as the handleshaft 850 of the handle assembly is coupled to (moves downward in acounterclockwise direction in FIGS. 8C and 8G) the coupling body 829 ofthe switch assembly.

FIG. 8B shows a side view of the handle shaft 850 (and more specificallythe male coupling element 852) of the handle assembly reaching thebottom end of the angled terminus 831, so that the male coupling element852 is in parallel with the slotted portion 833 of the switch assembly.FIG. 8D shows a side view of the handle shaft 850 (and more specificallythe male coupling element 852) of the handle assembly coupled to thecoupling body 829 (and more specifically the slotted portion 833) of theswitch assembly. Specifically, FIG. 8D shows the male coupling element852 coupled to the slotted portion 833 when the door of the enclosure isfully coupled to (closed against) the enclosure body. In other words,the male coupling element 852 is moving downward toward the bottom ofthe slotted portion 833 of the switch assembly relative to what is shownin FIG. 8B. The switch in FIG. 8D remains in the open position.

FIG. 8E shows a side view of the handle shaft 850 (and more specificallythe male coupling element 852) of the handle assembly coupled to thecoupling body 829 (and more specifically the slotted portion 833) of theswitch assembly. In this case, the switch position has been changed tothe closed position, causing the handle assembly and the switch assemblyto rotate in tandem by 90 degrees.

Because the one or more hinges that couple the door of the enclosure tothe enclosure body are positioned to the left of the actuator system800, and because of the orientation of the male coupling element 852coupled to the slotted portion 833 (a side of the female couplingelement 830, and not the slotted portion 833, faces the hinge), theslotted portion 833 prevents the male coupling element 852 fromdisengaging when the switch (and thus the handle shaft 850 and thecoupling body 829) are in the closed position. Specifically, when theswitch (and corresponding components of the switch assembly and thehandle assembly) is in one or more positions (e.g., the closedposition), the male coupling element 852 forms one or more frictionpaths (contacts) with the slotted portion 833 of the female couplingelement 830. As a result, in such positions, the friction paths(contacts) prevent the male coupling element 852 from disengaging fromthe slotted portion 833 of the female coupling element 830. In thiscase, the sides of the female coupling element 830 that extend above andform the slotted portion 833 act as a barrier that prevent the malecoupling element 852 from leaving the slotted portion 833 when theswitch is in the closed position.

As discussed above, the female coupling element 830, the slotted portion833, and/or the male coupling element 852 may be configured withadditional features (e.g., a pin, protruding linear component, a slot)so that the slotted portion 833 of the female coupling element 830engages the male coupling element 852 of the handle shaft 850 when thehandle shaft 850 and the coupling body 829 are in one or more certainpositions (e.g., corresponding to when the switch is in a closedposition) and so that the slotted portion 833 of the female couplingelement 830 is disengaged from the male coupling element 852 of thehandle shaft 850 when the handle shaft 850 and the coupling body 829 arein one or more certain other positions (e.g., corresponding to when theswitch is in an open position).

FIG. 8F shows a side view of the handle shaft 850 (and more specificallythe male coupling element 852) of the handle assembly coupled to thecoupling body 829 (and more specifically the slotted portion 833) of theswitch assembly. In this case, the switch position has been returned tothe open position, causing the handle assembly and the switch assemblyto rotate in tandem by 90 degrees in the opposite direction from FIG.8E. As the door is hingedly separated from the enclosure body (opens),the position of the vertical axis of the shaft assembly becomes out ofline with (not parallel to) the vertical axis of the handle assembly.

Because the hinge that couples the door of the enclosure to theenclosure body is positioned to the left of the actuator system 800, andbecause of the orientation shown in FIG. 8F of the male coupling element852 coupled to the slotted portion 833 (the opening of the slottedportion 833 facing the hinge), the slotted portion 833 disengages themale coupling element 852 when the switch (and thus the handle shaft 850and the coupling body 829) are in the open position. In this case, thesides of the female coupling element 830 that extend above and form theslotted portion 833 are not in the path of the male coupling element852, and so the male coupling element 852 is free to leave the slottedportion 833 when the fastening devices coupling the door to theenclosure body are removed and when the switch is in the open position.

EXAMPLE 2

Consider the following example, shown in FIGS. 9A through 9C, whichdescribes an actuator system 900 in accordance with one or moreexemplary embodiments described above. FIG. 9A shows a cross-sectionalside view of a portion of a handle assembly 949 and a switch assembly929. Specifically, the handle assembly 949 of FIG. 9A includes a handleshaft 950. The handle shaft 950 includes a male coupling element 952that is elongated and has a slot 954 formed between two fingers 953. Theslot 954 is open at the bottom of the male coupling element 952 andextends vertically upward to where the fingers 953 begin. The fingers953 may be of the same length or different lengths. The slot 954 isconfigured to receive a pin 936 of the female coupling element 933 ofthe coupling body 930.

The portion of the switch assembly shown in FIG. 9A includes a couplingbody 930 and a switch shaft 934. The coupling body 930 includes a femalecoupling element 933 and a pin that extends orthogonally from an innerwall of the female coupling element 933. When the handle shaft 950 ofthe handle assembly 949 is coupled to the coupling body 930 of theswitch assembly 929, the pin 936 of the female coupling element 933 ispositioned within the slot 954 of the male coupling element 952 when thehandle shaft 950 and the coupling body 930 (and thus the switch) are inone or more positions (e.g., the closed position). Further, when thehandle shaft 950 and the coupling body 930 (and thus the switch) are inone or more other positions (e.g., the open position), the pin 936 ofthe female coupling element 933 is positioned outside of the slot 954 ofthe male coupling element 952.

FIG. 9B shows a side view (not in cross section) of the actuator system900 shown in FIG. 9A. Thus, FIG. 9B shows the outer side of the femalecoupling element 933. In addition, the pin 936 is shown traversing theouter side of the female coupling element 933. In one or more exemplaryembodiments, the pin 936 is coupled to both sides of the female couplingelement 933 and traverses the slotted portion (not shown in FIG. 9B).The angled terminus 931 of the female coupling element 933 is also shownin FIG. 9B.

FIG. 9C shows a front view of the actuator system 900. The fingers 953of the male coupling element 952 are shown to be substantially similarin length. Further, the fingers 953 have an angled terminus thatcompliments the angled terminus 931 of the female coupling element 933.In such a case, the angled terminus of the fingers 953 of the malecoupling element 952 and the angled terminus 931 of the female couplingelement 933 work together to align the handle assembly 949 as the handleshaft 950 is being coupled to the coupling body 930.

EXAMPLE 3

Consider the following example, shown in FIGS. 10A and 10B, whichdescribes an actuator system 1000 in accordance with one or moreexemplary embodiments described above. In FIGS. 10A and 10B, thecoupling body 1029 of the switch assembly includes a switch shaft 1034and a female coupling element 1030. The female coupling element 1030includes an angled terminus 1031 and a slotted portion 1033. Theseelements of the switch assembly in FIGS. 10A and 10B are substantiallysimilar to the corresponding elements of the switch assembly describedabove with respect to FIGS. 8A through 8G.

A portion of the handle assembly shown in FIGS. 10A and 10B include ahandle shaft 1050, which includes a male coupling element 1052. The malecoupling element 1052 includes an extended arm 1054 that protrudes fromone or more sides of the male coupling element 1052. The extended arm1054 may be a separate element coupled to the male coupling element1052. Alternatively, the extended arm 1054 and the male coupling element1052 may be a single piece. The height of each extended arm 1054 mayvary. Here, the height of the extended arm 1054 is approximately halfthe height of the male coupling element 1052. In one or more exemplaryembodiments, the combination of the male coupling element 1052 and theextended arm 1054 are configured to be positioned inside the femalecoupling element 1033 so that the position of the handle correspondswith the position of the switch.

In FIG. 10A, the extended arm 1054 and/or the male coupling element 1052contact the angled terminus 1031 of the female coupling element 1030. Asthe handle assembly moves toward the switch assembly (i.e., as the doorof the enclosure closes), the slope of the angled terminus 1031 alignsthe combination of the extended arm 1054 and the male coupling element1052 in a position that corresponds to the position of the switch. FIG.10B shows the extended arm 1054 and the male coupling element 1052properly oriented and seated within the female coupling element 1030when the door to the enclosure is closed. In such a case, the shaft 1050(as well as the rest of the handle assembly) is in the position thatcorresponds to the position of the switch (as well as the rest of theswitch assembly).

EXAMPLE 4

Consider the following example, shown in FIGS. 11A and 11B, whichdescribes an actuator system 1100 in accordance with one or moreexemplary embodiments described above. In FIGS. 11A and 11B, thecoupling body 1129 of the switch assembly includes a switch shaft 1134and a female coupling element 1130. The female coupling element 1130includes an angled terminus 1131 and a slotted portion 1133. Theseelements (except for the slotted portion 1133, described below) of theswitch assembly in FIGS. 11A and 11B are substantially similar to thecorresponding elements of the switch assembly described above withrespect to FIGS. 8A through 8G.

In FIGS. 11A and 11B, the slotted portion 1133 is a hole that traversesat least part of the female coupling element 1130. For example, theslotted portion 1133 may be a hole that begins on an outer side of thefemale coupling element 1130 and ends at some point inside the femalecoupling element 1130. The size of the slotted portion 1133 of FIGS. 11Aand 11B may be configured to accommodate the male coupling element 1152of the handle shaft 1150. In this case, the male coupling element 1152is a hook that is fixedly coupled to the handle shaft 1150.

As with any exemplary embodiment described herein, the male couplingelement 1052 may be a separate component that is coupled to the handleshaft 1150. In such a case, the male coupling element 1052 may becoupled to the handle shaft 1150 using one or more of a number ofmethods, including but not limited to welding, using a fastening device(e.g., a screw), and a threaded coupling. Alternatively, the malecoupling element 1052 and the handle shaft 1150 may be a single piece.In one or more exemplary embodiments, the radius of the male couplingelement 1152 of FIGS. 11A and 11B corresponds to the pivot angle of thehinge connecting the door to the enclosure body.

In FIG. 11A, the male coupling element 1152 contacts the angled terminus1131 of the female coupling element 1130. As the handle assembly movestoward the switch assembly (i.e., as the door of the enclosure closes),the slope of the angled terminus 1131 aligns the male coupling element1152 in a position that corresponds to the position of the switch. As aresult, once the handle assembly is properly aligned with the switchassembly, the male coupling element 1152 is properly positioned toengage the slotted portion 1133 of the female coupling element 1130.

FIG. 11B shows the male coupling element 1152 properly oriented andseated within the female coupling element 1130 when the door to theenclosure is closed. In such a case, the shaft 1150 (as well as the restof the handle assembly) is in the position that corresponds to theposition of the switch (as well as the rest of the switch assembly).

One or more exemplary embodiments provide for an actuator system.Specifically, the actuator system provides for self-aligning a handleassembly with a switch assembly as a door of an enclosure is closed,where closing the door causes the handle assembly to couple to theswitch assembly. Components (e.g., handle, shaft) of the handle assemblymay be in any position of a number of positions before the shaft of thehandle assembly is coupled to the coupling body of the switch assembly.One or more exemplary embodiments further provide for mechanicallycoupling the shaft of the handle assembly to the coupling body of theswitch assembly. Specifically, the male coupling element of the shaft iscoupled to the female coupling element of the coupling body.

One or more exemplary embodiments further provide for disengaging (ordecoupling) the male coupling element of the shaft from the femalecoupling element of the coupling body when the switch (and thus thecomponents of the handle assembly and the switch assembly) are in one ormore of a number of decoupling positions. When the switch is not in theone or more of the number of decoupling positions, the male couplingelement of the shaft remains coupled to the female coupling element ofthe coupling body. In other words, if the switch is not in the one ormore of the number of decoupling positions, the door to the enclosurecannot be opened (or the cover cannot be separated from the enclosurebody) because the handle assembly remains coupled to the switchassembly. Consequently, a safety feature is added by preventing a userfrom accessing energized components inside the enclosure.

Although an actuator system for operating a switch located inside anexplosion-proof enclosure is described with reference to preferredembodiments, it should be appreciated by those skilled in the art thatvarious modifications are well within the scope of an actuator systemfor operating a switch located inside an explosion-proof enclosure. Fromthe foregoing, it will be appreciated that an embodiment of an actuatorsystem for operating a switch located inside an explosion-proofenclosure overcomes the limitations of the prior art. Those skilled inthe art will appreciate that an actuator system for operating a switchlocated inside an explosion-proof enclosure is not limited to anyspecifically discussed application and that the exemplary embodimentsdescribed herein are illustrative and not restrictive. From thedescription of the exemplary embodiments, equivalents of the componentsshown therein will suggest themselves to those skilled in the art, andways of constructing other embodiments of an actuator system foroperating a switch located inside an explosion-proof enclosure willsuggest themselves to practitioners of the art. Therefore, the scope ofan actuator system for operating a switch located inside anexplosion-proof enclosure is not limited herein.

What is claimed is:
 1. An actuator system for operating a switch, theactuator system comprising: a first shaft of a handle assembly, whereinthe first shaft has a length and comprises: a first shaft end portiondisposed at one end of the length of the first shaft, wherein the firstshaft end portion couples to a handle of the handle assembly; and asecond shaft end portion disposed at an opposing end of the length ofthe first shaft, wherein the second shaft end portion comprises a firstcoupling element; and a coupling body of a switch assembly, wherein thecoupling body comprises: a second shaft; a first coupling end portioncoupled to and disposed at a first end of the second shaft, wherein thefirst coupling end portion is coupled to and engages the switch of theswitch assembly; and a second coupling end portion comprising a secondcoupling element, wherein the second coupling element is disposed at asecond end of the second shaft, wherein the second coupling elementcouples to the first coupling element of the second shaft end portion,wherein the first shaft and the second shaft are axially aligned witheach other along the length of the first shaft when the first couplingelement and the second coupling element are coupled to each other,wherein the first coupling element self-aligns, with respect to thesecond coupling element, the first shaft to a first position of aplurality of positions as the first shaft couples to the coupling body,wherein self-aligning the first coupling element with respect to thesecond coupling element prevents misalignment of the first shaft,wherein the plurality of positions corresponds to a plurality of switchpositions, wherein the first shaft, the first coupling element, thefirst shaft end portion, and the second shaft end portion remain coupledto each other and to a remainder of the handle assembly when the firstshaft is uncoupled from the coupling body, wherein the second shaft, thesecond coupling element, the first coupling end portion, and the secondcoupling end portion remain coupled to each other and to a remainder ofthe switch assembly when the first shaft is uncoupled from the couplingbody, and wherein, when the first shaft is coupled to the coupling body:the first coupling element and the second coupling element are preventedfrom disengaging when the first shaft and the coupling body are in asecond position of the plurality of positions, and the first couplingelement and the second coupling element disengage when the first shaftand the coupling body are in the first position.
 2. The actuator systemof claim 1, wherein the first coupling element comprises a slottedportion and an angled terminus, wherein the slotted portion receives andengages the second coupling element when the first shaft is coupled tothe coupling body, wherein the slotted portion prevents the secondcoupling element from disengaging when the first shaft and the couplingbody are in the second position, and wherein the slotted portiondisengages the second coupling element when the first shaft and thecoupling body are in the first position.
 3. The actuator system of claim2, wherein the second coupling element comprises a slot formed therein,wherein the first coupling element further comprises a pin extendingorthogonally therefrom, wherein, when the first shaft is coupled to thecoupling body, the pin is positioned within the slot when the firstshaft and the coupling body are in the second position, and wherein thepin is positioned outside the slot when the first shaft and the couplingbody are in the first position.
 4. The actuator system of claim 1,wherein the first shaft traverses an opening in a door of an enclosure,wherein the switch and the coupling body are positioned within theenclosure, and wherein the handle is located outside the enclosure. 5.The actuator system of claim 4, wherein the door of the enclosure cannotbe separated from an enclosure body of the enclosure when the handle isin the second position.
 6. The actuator system of claim 5, wherein thedoor of the enclosure is hingedly coupled to the enclosure body on oneside of the enclosure body.
 7. The actuator system of claim 1, furthercomprising: a plurality of fastening devices that traverse a pluralityof fastening device apertures along a perimeter of the door, wherein theplurality of fastening devices, when coupled to the plurality offastening device apertures, couple the door to the enclosure and preventthe door from separating from the enclosure, and wherein the doorseparates from the enclosure when the plurality of fastening devices areremoved from the plurality of fastening device apertures and when thehandle is in the first position.
 8. The actuator system of claim 1,wherein the first shaft and the coupling body are not parallel to eachother.
 9. A method for operating a switch, the method comprising:rotating a handle, mounted on an outer surface of a door coupled to anenclosure body, from a first position of a plurality of positions to asecond position of the plurality of positions; and separating, afterrotating the handle to the second position, the door from the enclosurebody, wherein the handle is coupled to a first shaft comprising alength, a first shaft end portion disposed at one end of the length ofthe first shaft and for coupling to the handle, and a second shaft endportion disposed at an opposing end of the length of the first shaft,wherein the second shaft end portion comprises a first coupling element,wherein the first coupling element couples to a second coupling elementdisposed on a second shaft of a coupling body, wherein the first shaftis axially aligned with the second shaft of the coupling body when thefirst coupling element and the second coupling element are coupled toeach other, wherein the first coupling element self-aligns, with respectto the second coupling element, the first shaft to the second positionof the plurality of positions as the first shaft couples to the couplingbody, wherein self-aligning the first coupling element with respect tothe second coupling element prevents misalignment of the first shaft,wherein the coupling body further comprises a third coupling elementcoupled to and disposed on the second shaft, wherein the third couplingelement is coupled to and engages the switch, wherein the plurality ofpositions corresponds to a plurality of switch positions, wherein thefirst coupling element and the second coupling element are preventedfrom disengaging when the first shaft and the coupling body are in thefirst position, wherein the first shaft, the first coupling element, thefirst shaft end portion, and the second shaft end portion remain coupledto each other and to the handle when the first shaft and the couplingbody are in the first position, wherein the second shaft, the secondcoupling element, and the third coupling element remain coupled to eachother and to a remainder of the switch when the first shaft and thecoupling body are in the first position, and wherein the first couplingelement and the second coupling element disengage when the first shaftand the coupling body are in the second position.
 10. The method ofclaim 9, wherein the first coupling element comprises a slotted portionand an angled terminus, wherein the slotted portion receives and engagesthe second coupling element of the second shaft end portion when thefirst shaft is coupled to the coupling body, wherein the slotted portionprevents the second coupling element from disengaging when the firstshaft and the coupling body are in the first position, and wherein theslotted portion disengages the second coupling element when the firstshaft and the coupling body are in the second position.
 11. The methodof claim 10, further comprising: coupling, prior to rotating the handle,the door to the enclosure body; and rotating the handle from the secondposition to the first position, wherein the angled terminus of the firstcoupling element self-aligns, with respect to the second couplingelement, the first shaft to the second position of the plurality ofpositions as the first shaft couples to the coupling body, and whereinthe slotted portion receives, after the angled terminus aligns the firstshaft, the second coupling element.
 12. The method of claim 9, whereinthe first position of the handle corresponds to a closed switchposition, and wherein the second position of the handle corresponds toan open switch position.
 13. The method of claim 9, wherein the secondcoupling element further comprises a slot formed therein, wherein thefirst coupling element further comprises a pin extending orthogonallytherefrom, wherein the pin is positioned within the slot when the handleis in the first position, and wherein the pin is positioned outside theslot when the handle is in the second position.
 14. The method of claim9, wherein the first shaft traverses an opening in the door, wherein theswitch and the coupling body are positioned within the enclosure body,and wherein the handle is located outside the enclosure on an outersurface of the door.
 15. The method of claim 14, wherein the door cannotbe separated from the enclosure body when the handle is in the firstposition.
 16. The method of claim 9, wherein the switch is a disconnectswitch, wherein the plurality of switch positions comprise an openposition and a closed position, and wherein a plurality of designationson a switch position indicator comprises on and off.
 17. The method ofclaim 9, wherein the door coupled to the enclosure body creates anexplosion-proof enclosure.
 18. The method of claim 17, wherein the dooris coupled to the enclosure body using a plurality of fastening devicesthat traverse a plurality of fastening device apertures along aperimeter of the door and an outer surface of the enclosure body,wherein the door is hingedly coupled to the enclosure body using one ormore hinges located on one side of the enclosure body, and wherein thedoor separates from the enclosure body, while coupled at the one or morehinges, when the plurality of fastening devices are removed from theplurality of fastening device apertures and when the handle is in thesecond position.
 19. An actuator system for operating a switch, theactuator system comprising: a first shaft of a handle assembly, whereinthe first shaft has a length and comprises: a first shaft end portiondisposed at one end of the length of the first shaft, wherein the firstshaft end portion couples to a handle of the handle assembly; and asecond shaft end portion disposed at an opposing end of the length ofthe first shaft, wherein the second shaft end portion comprises a firstcoupling element; and a coupling body of a switch assembly, wherein thecoupling body comprises: a second shaft; a first coupling end portioncoupled to and disposed at a first end of the second shaft, wherein thefirst coupling end portion is coupled to and engages the switch of theswitch assembly; and a second coupling end portion comprising a secondcoupling element, wherein the second coupling element is disposed at asecond end of the second shaft, wherein the second coupling elementcouples to the first coupling element of the second shaft end portion,wherein the first shaft and the second shaft are axially aligned witheach other along the length of the first shaft when the first couplingelement and the second coupling element are coupled to each other,wherein the first coupling element self-aligns, with respect to thesecond coupling element, the first shaft to a first position of aplurality of positions as the first shaft couples to the coupling body,wherein self-aligning the first coupling element with respect to thesecond coupling element prevents misalignment of the first shaft,wherein the first shaft, the first coupling element, the first shaft endportion, and the second shaft end portion remain coupled to each otherand to a remainder of the handle assembly when the first shaft isuncoupled from the coupling body, wherein the second shaft, the secondcoupling element, the first coupling end portion, and the secondcoupling end portion remain coupled to each other and to a remainder ofthe switch assembly when the first shaft is uncoupled from the couplingbody, and wherein the plurality of positions corresponds to a pluralityof switch positions.